Position detecting device and synchronous motor driving device using the same

A motor driving device comprising:

• a semiconductor device for converting DC power to AC power or converting AC power to DC power;
• a position detecting device for detecting a motor pole position by using two or more sensor signals;
• a position detector calculator configured to execute position calculation by inputting basic-wave component signals in said sensor signals,
• wherein said position detector calculator is configured to extract said sensor signals in a range between predetermined first and second determination values, thereby converting extracting signals, and said first determination value is larger than said second determination value, and is smaller than a maximum value of said sensor signal, and said second determination value is larger than a minimum value of said sensor signal;
• and
• said means for correcting so as to reduce position detection error by calculating signal information representing at least one of gain, an offset and a phase by using a signal between said first determination value and said second determination value in said extracting signal and making correction based on the signal information.

A motor driving system comprising:

• a semiconductor device for converting from DC power to AC power or converting from AC power to DC power;
• a position detecting device for detecting a motor pole position by using two or more sensor signals;
• a sensor unit for generating said sensor signal;
• a position detector for executing position calculation by inputting basic-wave component signals in said sensor signals,
• wherein said position detector extracts said sensor signals in a range between predetermined first and second determination values, thereby converting extracting signals, and said first determination value is larger than said second determination value, and is smaller than a maximum value of said sensor signal, and said second determination value is larger than a minimum value of said sensor signal;
• and
• means for correcting to reduce position detecting error by calculating signal information representing at least one of a gain, an offset and a phase by using a signal between said first determination value and said second determination value in said extracting signal and making correction based on the signal information.

A permanent-magnet synchronous motor driving device comprising:

• a position detecting device for detecting a motor pole position by using two or more sensor signals;
• a motor controller for producing a PWM drive signal based on a position detected value detected by said position detecting device, and outputting the PWM drive signal to an inverter, thereby driving a permanent-magnet synchronous motor;
• a sensor unit for generating said sensor signal;
• a position detector for executing position calculation by inputting basic-wave component signals in said sensor signals,
• wherein said position detector extracts said sensor signals in a range between predetermined first and second determination values, thereby converting extracting signals and said first determination value is larger than said second determination value, and is smaller than a maximum value of said sensor signal, and said second determination value is larger than a minimum value of said sensor signal;
• and
• means for correcting to reduce position detection error by calculating signal information representing at least one of a gain, an offset and a phase by using a signal between said first determination value and said second determination value in said extracting signal and making correction based on the signal information.